I've got a couple of ideas. First, understand that eConnect talks to the SQL Server via the eConnect service.
Next, understand that if you code is not running on the server, you have to get DCOM up and running. I loathe settin up DCOM so much that I won't support that method. What I do is ALWAYS build a web service that sits on the SQL Server, my VB apps submit text eConnect docs to the SQL Server. That way, I never have to mess with DCOM <shudders>
So, for our purposes here, make sure that whatever code you are talking about is running ON the SQL server. If it's not, I don't support that. <smiles>
Next, get the username and password that the eConnect service is running under. It should be a domain account (but it doesn't have to be). Look in SQL Server security, make sure that use has rights to the database in question and is a member of the DYNGRP role for that database.
That's usually what causes that error.